For certain applications, it is desirable to place sensors in hostile environments, such as environments having extremes of temperature, high levels of radiation, or in which very little power is available, leading to very low supply voltages. A difficulty in such hostile environments is that circuits may no longer operate correctly in view of the parameter variations resulting from the environment. For example, the current leakage in a circuit increases exponentially with temperature, leading to failure when the temperature reaches a certain level. For example, sensors may be used to control and/or monitor the operation of aeroplane engines, where the temperature may rise as high as 250° C., leading to high current leakage and potential failures.
While some solutions have been proposed for providing sensor interfaces that are to some extent robust against errors resulting from the environment, for certain applications there is a need for a sensor interface providing greater precision in hostile environments.